The present invention relates to a method for delivering coffee beverages from capsules designed to be extracted under pressure and containing a substance for the preparation of a coffee beverage.
Coffee cups can be produced from filter coffee machines. However, as a result of a “light” extraction of the coffee, the resulting extract usually has low coffee solids concentration, a low aroma profile, and little or no “crema” on the top.
Capsules designed to be extracted under pressure and containing a substance for the preparation of a beverage exist on the market. They provide a better extraction of coffee, i.e., a higher “extraction yield”, more aroma and a better “crema”, more convenience in operation and they ensure freshness of the substance contained therein. As a result, the delivery of freshly extracted beverages of constant quality is better ensured.
For instance, the actual system commercialized under the trademark “Nespresso®” is appreciated for producing good quality short cups of coffee and long cups of coffee. A short cup of coffee extract is defined as containing less than 50 grams of coffee liquid extract in the cup and more specifically about 40 g for the espresso type and about 25 g for the ristretto type. Due to the high pressure extraction conditions maintained in the capsule, in the order of 10-20 bar the liquid extract which is delivered can be given desirable quality attributes in term of coffee yield, coffee solids and “crema” and within a delivery flow time which is found acceptable for the user. Therefore, typically a short coffee extract can be delivered within a flow time of between 20 and 45 seconds in order to provide a desired body, taste, flavour and crema.
There is a need to deliver a short coffee extract in a reduced flow time however maintaining the quality attributed relatively unchanged.
There is also a need to deliver a short coffee extract with a stronger taste.
The present invention aims at a significant improvement to the capsule system of the prior art. In particular, a main object is to reduce flow time when delivering a short coffee extract from the capsule while at the same time maintaining or even improving the quality attributes of the coffee, in particular, a desirable strength (e.g. expressed by its “extraction yield”) and also a sufficient thickness and texture of crema.